Mechanical impulse repeater



Jan. 30, 1940. J, w. McCLEW El AL 2,188,461

- MECHANiCAL IMPULSE REPEATER Filed May 15, 1936- 3 Sheets-Sheet l Patented Jan. 30, 1940 l MECHANICALIMPULSE-BEPEATEB- John William Mcillewand Cecil Robert 'Wood- Y land, Liverpool, England, assignors-to Assoolated Telephone and Telegraph Company, Chicago,:lll., a corporation Delaware Application May 15, 1930, :Serial No. rass'o In Great Britain Jnne-11,'1935 g '24 Claims. {(1179-16) UNITED. STATES Pars-NT OFFICE ing place entirely independently. The attainment of this object-is simplified by the use of a .reglstering and sending device in which the length of a train or .outgoing impulses is determined by a mechanical marking corresponding to the received train rather than by an electrical marking as is more usuaL- A device of this type is employed in carrying out the invention and for convenience it will hereafter be referred to ass mechanical impulse repeater.

According-to one feature of the invention-in a mechanical impulse repeater foruse in 'teler v a resetpin '24, carried by the transmitting disc,

phone or like impulse sending systems, in accordance with the number of impulses in each of a succession of trains of incoming impulses appropriate ones of a pluralityioi movableimembers are caused to move from their normal position and thereby determine the number of outgoing impulses to be transmitted in successive trains, each member on restoration to normal enabling the transmission of the next train of outgoing impulses to take place.

According to another feature of the invention a mechanical impulse repeater for use in telephone or like impulse sending systems comprises in combination an electromagnet arranged togrespond to incoming impulses and to control the operation of a setting device in accordance therewith, a device arranged to be moved at the endof a train of impulses to effect a marking in ac- A further feature of the invention is that in a mechanical impulse repeater for use in telephone or like impulse sending systems, incoming trains of impulses operate as single registering device which subsequently controls the transmission ofvsimilar trains of impulses correct as regards speed and ratio, the registering device being effective to register a train or trains of impulses whilea previous train is still being transmitted.

The invention will be better understood from the following description of one method of carryingit intoefl'ect reference being had to the accompanying-drawings comprisingFigs. 1-5.

Fig. .1 shows suitable circuit connections for a repeater of the mechanical construction according'to atheiinvention, and the remainingflgures 6 i show various views of a practical form of the mechanism, of which Fig. 2 is *a front view of the device showing a .transmittingdisc l3 mounted for counter-clockwise rotation; a-pin-resetting lever 45 mounted l0 'uponthe disc, a set ot :impulsing springs 50 operated by the cam 29 during rotation of the transmitting disc, and "a fly-ball governor II for :controllingthe speed of rotation of the cam;

3 is :a rear view or the device showing a 15 ratchet wheel 8, an impulse receiving magnet I for stepping the ratchet wheel, a pin-settingior marking) magnet 2 with itsassociated armature 8 :and a pin-resetting (or transmitting) magnet 3 with its associated armature-ill. .20 Fig.4 :is-ea planiview of the device, showing pathdescribed by the reset pin during rotation of the transmitting disc). thereby preventing rotation-oizthe disc. V Fig. 5 is a sectional view taken along the line 'V-V oi 4 showings. pin-setting lever 38 so which isaflixed to the ratchet wheel 8 for rotation thereby and which be actuated [by armature 6 0! the pin-setting magnet to displace pin it to the left and consequently into the path of the reset pin 24. This figure alsoshows the 35 mechanism including a rod 36 for actuatina'fihe resetting lever 45 and the reset pin 24 responsive toenergization of the pin-resetting magnet thereby to restore :a displaced stop pin to the right and permit the transmitting disc to resume its 40 rotation.

Referring now ingreater detail to the mechanical construction of the impulse correcting device asshown in Figs. 2-5, it will be seen that the I fixed disc i2 takes the form of a rectangular U- 45 shaped mounting plate carrying a circle of displaceable'p'ins ll. f.The impulse receiving disc 1 is a ratchet wheel 8 having associated with it a movable collar 32 which by means of the collar pins. 34 can be caused to tilt the pin-settinggo lever 38 about its pivot 33 when the marking or pin-setting magnet 2 actuates its armature 8; In Fig. 5 armature 6 is shown in the operated position in which lever 39 is clear of the pins l4.

Theratchet wheel 9 is secured to one end or 5 a tubular spindle III supported in a bush 31 which is secured to the frame plate I21. The opposite end of the spindle is fastened to the centre of a clock spring II contained in a cup II secured to the transmitting disc or gear wheel I3 which is carried on ball bearings I5 also mounted on the bush 31.

The receiving magnet I responds to incoming impulses and rotates the ratchet wheel 9 step by step by means of the armature 26 and' the pawl 21. The movement of the ratchet wheel rotates the shaft 35 and stores up energy i'n'the clock spring II secured to the other end of the spindle. The movement of the armature 26 takes place against the tension of the spring 4 while the pawl 21 is kept in engagement with the ratchet wheel 9 by the spring 38. When the magnet is de-energised at the end of each impulse, the

ratchet wheel 9 is rotated one step by the action of the spring 4. The travelof the armature and pawl can be adjusted by the eccentric stops 23 and 28 respectively. The marking magnet 2 is energised throughout each series of impulses and by means of its armature 8 which is'provided with a forked end slides the collar 32 along the shaft 35 so as to tilt the pin-setting lever 39 out of engagement with the pins I4 against the action of spring 40. Since the marking magnet 2 remains operated throughout the series of impulses, the lever 39 which is secured to the shaft 35 does not obstruct its movement of enga any of the pins.

At the end of the series of impulses, the ratchet wheel 9 is retained by the fixed detent 8 in the position to which it has been set, and when'magnet 2 de-energizes armature 6 restores thereby permitting lever 33 to move to the left under the action of spring 40. Lever 39 then pushes the particular stop pin opposite which it has stopped throughthe plate I2 into the path of the reset pin 24 which is attached to but insulated from the transmitting gear wheel I3. Gear wheel I3 is prevented from following the ratchetwheel 3 under the influence of the spring I1 because the reset pin 24 is held by the stop pin pushed into its path at the completion of regeneration on the previous call. This can be better appreciated from Fig. 4 since in Fig. 5 for purpose of clarity the associated pin has been shown in the normal position which would allow the transmitting disc I3 to rotate. It will be noticed from Fig. 4 that the end of the reset pin is stepped and the purpose of this will be more fully appreciated later;

The transmitting magnet 3 is provided with an armature projection I 0 which is insulated from the armature proper and which when operated tilts the insulated pin reset lever 45 about its pivot 46 to the right by means of an insulated pin 36 taken through the hollow spindle 35. Electrical contact between pin 36 and the spindle is prevented by the use of insulating washers 22 at each end of the spindle and contact between the spindle and the pin reset lever 45 is prevented by use of an insulating stud 20 mounted on the left-hand end of the spindle. The pin 36 is electrically connected to the outside ofl-normal spring I6 which is insulated from the frame and co-operates with the inside spring 2| which" is electrically connected to the frame. Both these springs are secured to the spindle 35 and they are permitted to close by the insulated buffer as soon as the spindle 35 is rotated by the operation of the magnet I. The buffer 4| is secured to the insulated bracket 42 supporting the reset pin 24 which is initially prevented from rotating by its engagement with the appropriate pin l4.

Electrical connection to the pin 24 is made by way of the spring 26 and the pin reset lever 46. The frame plate I2 is insulated from the main .mounting plate 44 by a thin layer 43 of fibre or like insulating'materlal.

'When the magnet 3 is operated which as will be described later takes place due to the completion of a circuit over the normally closed transmitting magnet springs I, armature extension I0, pin 36, off-normal springs I6 and 2|, digit stop pin I4, reset pin 24. and spring 25, the pin reset lever 45 pushes the reset pin 24 to the right and this resets the digit stop pin to its normal position out of the path of the reset pin.

The gear wheel I3 is prevented from moving as long as the magnet 3 is energized since the stepped position of the reset pin 24 still engages the restored pin I4. When the magnet is deenergised however, the reset pin is restored to normal by the helical spring 41, the gear wheel I3 is freed and under the influence of the stored energy in the spring I'I it rotates in the same direction as the ratchet wheel 9 until the reset pin 24 encounters the digit stop pin which was displaced at the end of the first digit. The gear 'wheel' I3 drives a pinion carrying an impulse cam 29 which during" rotation actuates the impulse spring 50 and transmits a train of impulses similar to those received except they will now be of the correct character as regards ratio and speed. The speed is controlled by an adjustable driven through worm. wheel I8. The governor cup is threaded and can thus be moved axially by rotating it. The inside of the cup is slightly conical and hence altering its position willalter the radius at which the governor wings engage and thus alter the speed. The governor cup is locked in any desired position by a fiat spring 30 hearing on'its serrated surface. Thepurpose of the holes provided in gear wheel I3 as shown in Fig. 2 is to lighten it and thus reduce its inertia. When the reset pin 24 on gear wheel I3 encounters the stop pin corresponding to the first digit, the rotation is arrested and an electrical circuit through'the pins is again completed to initiate a timing operation for determining the length of interdigital pause. pired, magnet 3 is again energised and the gear wheel I3 is again released and rotates untilthe reset pin 24 reaches the stop pin corresponding to the next digit, thus sending a series of regenerated impulses corresponding to the second digit. The process is repeated until all the digits have been dealt with when the gear wheel I3 will again catch up with the ratchet wheel 9 and the off-normal springs I6 and 2| are opened to prevent further sending.

Considering how the operation of the device with relation 'to the repeater circuit shown in Fig. 1, when the repeater is taken into use, relay A operates over the line conductors and at armafiy-ball governor 3| carried on bracket I9 and- After this has exture aI operates relay B. I As a result, armature pletes'the outgoing loop circuit including relays D and I so as to prepare the distant switch for operation.

Upon receipt of the first series of impulses,

the impulses at armature al to the receivin magnet RCM of the impulse correcting device in parallel with relay C. It should be, mentioned that the ratchet wheel 9 is indicated in Fig. 1 by the disc R, the gear wheel I3 by the disc T and the pin-carrying frame member I2 by the disc F. The number of pins providedmay conveniently be 40 whichwill renderthe device capable of dealing with at least four digits at a time. The operation of the magnet RClV I serves to drive the disc R thus putting additional tension on the spring by which it is connected to the disc T. This disc is prevented from rotating because it is held against the pin displaced from the fixed disc F at the end of the last call. The disc R is driven by the magnet RCM on the release. drive principle so that before it commences to, move have energised the marking magnet MKM cor responding to magnet 2 in Figs. 2-5, which tilts the lever 38 carried by the disc R clear of the pins. Relays B and C are provided with copper slugs to enable them to remain continuously en-.

ergised during the stepping of disc R and accordingly the lever 39 is held clear of the pins during the whole movement corresponding to the first digit. No effect is yet produced however on the disc T.

At the end of the first digit the disc R .will have advanced a number of steps equal to the'numberv of impulses in the train and when relay C releases after its slow period, the marking magnet MKM isde-energised and allows the lever 39 to restore thereby pushinga corresponding .pin from thisdisc into the path of disc T. 'Furthermore'contacts mkm operated by the marking magnet will now close andsince the off-normal springs ON close as soon as the disc R rotates away from disc I, a circuit is now completed for operating relay BY which looks up at armature D112 independent of contacts mkm. Armature byl ,prepares a circuit for the transmitting magnet TRM,

armature b'y3 short circuits relays D and I "in order to provide better impulsing conditions for repeating regenerated impulses into the apparatus at the distant exchange, armature byl applies a further guard earthto the P conductor;

armature c115 provides a further earth to hold relay IP, while armature byS completes a circuit from earth, off-normal springs ON, fixed disc F and pin, insulated reset pin 24 in'disc T, contacts trm, and armature byB to short circuit relayhI P.

After a short interval relay IP releases and at armature ipl completes a circuit to energise the transmitting magnet TRM which thereupon moves the reset pin 24 to restore the movable pin v in the disc F against which it is resting. At-the same time the contacts trm remove the shortcircuit from relay IP.which immediately re-opcrates and releases the transmitting magnet at armature z'pl. The transmitting magnet thus only operates for a period sufficiently long to push the pin back to normal. Disc T is now freed from.

" disc F and it rotates due to the coil spring '11 until it'comes up against the stop pin ondiscF which was displaced at the end of the first digit.

Meanwhile the second digit will be in process of reception and the disc R will therefore be advanced to a'further positionwhere a further pin in disc F is pushed forward to'register the second digit.

It will be recalled that the in the form of a gear wheel 13 adapted to drive under the control of a suitable adjustable speed and when the called subscriber at the distant exchange removes his receiver, the batteryfeed to to condenser discharge. 'If the called subscriber ceiver before the mechanism has 'cornpleted'the disc T is actually governor IS a' cam 23. controlling the impulse springs IMP in the outgoing loop circuit and it" I that by a suitable 'adjustwill be clear therefore ment of the governor 29 it can be arranged that the regenerated impulses are of the correct speed 6' pause between the regenerated series of impulses is controlled by the release time of the relay 1? and the operation and release of the magnet TRM. 15 7 When all digits have been received, the disc R finally comes to rest and when all regenerated digits have been transmittedv the disc T'catches relay C will have operated and at armature cl will up with the disc R and comesIto' rest against the. final stop pin. In this position the off norm'al springs 0N again open and unlock relay BY and I armature by3 removes the, short-circuit from'the impedance bridge relays D andI. The repeater circuit is now prepared for speech transmission relays D and I over the junction from the distant exchange is reversed. The right-hand winding of the polarised'relay D is already energised from armature 2| and since the current fiow'in the two windings of the polarised relay D is now-in the same direction, relay D will operate and at arma- Y ture dl operate f relay DR. Armatures' drl and dr2 reverse the battery potential on the incoming 1 negative and positive conductors to give a supervisory signal to the calling apparatusa'nd armature dr3 operates relay BB. This relay at arma ture bbl shunts armature ip! in the negative speaking conductor, at armature bb4 locksitself up, at-armature bb2 further guards the? conductor, at armature bb3ope'ns the impulsing cir cuit to the regenerating mechanism in" order to prevent its operation shouldthecallin'g subscriber accidentally operate, the dial during conversa tion, and at. armature 'bb 5 disconnects relay IP. 45 Relays A, B, D, I, DR and BB remain operated during the" conversation,

When thecalling subscriber replaces his receiver, relay A' releases and disconnects relayB. I Relay B releases after a slight interval and opens the circuit of relays D and I and the former-"disconnects relay DR. After a further short inter l val, relay DR releases and disconnects relay BB.

- When relay BB releasesiafterits slow period; thet 1 guardearth is removed from the'P conductor to' release the preceding switches and free the re--- peater for further use. Relay DR is made slow operating by the use of. a copper slug=at the armature end in order to prevent it being-operated shouldtrelayl D beafiected by any kicksdue replaces his receiver first, relays D, I and DR arev released and relay BB is then dependent only on relayBL 5 Should the calling. subscriber replace his',re-

transmitting operation the incoming P conductor is guarded at armature by d until such time as the mechanism is ready to deal with another call, a .70;

It will be appreciated that there is no necessity to restore the impulse correcting device to normalsince it is arranged to resume its operation on the next call from the position it occupies at the termination of the previous one.

'It is to be understood that the invention is not limited to the details of construction employed, as modifications may be made in the impulse receiving arrangements and in the impulse transmitting means without departing from the spirit of the invention. For instance, a number of receiving devices instead of one may be employed each adapted to handle a single digit and a number of transmitting devices may be employed instead of one, in which case appropriate transfer arrangements would require to be provided to render each device operable successively in proper order and at the proper time. At the same time it is believed that the general construction shown provides a simple and more economical construction as it will simplify the mechanism and circuits. Similarly the length or the interdigital pause may be controlled by separate timing arrangements. Moreover though the invention has been described with reference to a'straightforward impulse repeater for regenerating direct current impulses, it is not limited to this use. For instance it could readily be arranged to convert alternating current impulses which might be of voice frequency into direct current impulses and vice versa. Furthermore the mechanical re generator might be employed in an incoming repeater instead of an outgoing repeater as shown in Fig. 1.

The use of this invention extends the impulsingiimits obtainable in that it may be used over long distance lines, having a mechanismat each end if both way' working is employed. Owing to the lightness of construction, the mechanism can successfully respond to a train of mutilated pulses and subsequently send out corresponding regenerated pulses which are correct as regards ratio and speed.

We claim:

1. In a repeater, a plurality bers each having a normal position, means for moving appropriate'ones of said members from their normal positions in accordance with the number of impulses in each 01, a series of trains of incoming impulses, means for transmitting outgoing impulses in successive trains, said moved members determining the number of outgoing impulses in each transmitted train, means for restoring each moved member to normal posi-' tion, and each member on restoration enabling the transmission of the next train of outgoing impulses to take place.

2. In a repeater, the combination of an electromagnet operated in response to incoming impulses, a setting device operated in accordance with the operationsof said electromagnet, a plurality of marking devices, a particular one of said marking devices selected in dependence upon the position occupied by the setting device at the end oi a train of impulses and would to efiect a marking, and .asecond electromagnet for initiating the transmission of a train of outgoing impulses in accordance with said marking.

3. In a repeater, a single registering device operated in accordance with a plurality of incoming trains of impulses, means for transmitting corresponding outgoing trains of impulses in accordance with the operated register device, and means for delaying the transmission of each outgoing train of impulses until the corresponding incoming train of impulses is fully received and registered.

of movable memtrains of impulses oi the same number, each outgoing train of impulses delayed until the corre- 'sponding incoming train has been fully stored,

and an electromagnetically-controlled device for determining the instant each outgoing train of impulses is to be transmitted.

5. In a repeater, a member operated responsive to successive trains of incoming impulses, a secdevice adapted to be driven at a constant rate of speed,-an impulse generatorcontrolled by said device for generating outgoing impulses, obstructing means moved into the path of said device in response to the operation of said registering means to effect a marking corresponding to the end of each incoming impulse train, and means for restoring the moved obstructing means to initiate operation of said device and generator a predetermined time after said obstructing means was moved by said registering means.

7. In a repeater. a single register device operated one step for each incoming impulse received and successively operated in accordance with a plurality oi incoming trains of impulses to register the same, means for transmitting corresponding outgoing trains of impulses in accordance with said registrations, said register device being effective to register an incoming train 01' impulses during the time a previously registered incoming train is being-transmitted.

8. In a repeater, a registering member operated step-by-step in response to incoming impulses, an impulse sender for transmitting outgoing impulses, a stop member carried by said sender moved over a path corresponding to that of the registering member, and a pin displaced in the path of said stop member by said registering member coming to rest after its step-by-step operation at the end of a series of incoming imated responsive to trains of incoming impulses, a

pulses for controlling the operation of said sender.

9. In a repeater as claimed in claim 1 including an electromagnet for restoring said movable members, a circuit for said magnet, and means for closing a point in said circuit in response to the completion of the transmission of an outgoing, train of impulses.

10. In a repeater as claimed in claim '7 having means for initiating the transmission of the outgoing trains of impulses after the registration of the first incoming train of impulses.

11. In a repeater as claimed in claim 1 including means for automatically introducing a pause of predetermined length between successive trains of outgoing impulses.

12. In arepeater as claimed in claim 5 including means for releasing said second member to enable the same to follow said first member to generate said outgoing impulses after the .termination of the corresponding incoming impulse train.

13. In a repeater, a registering member operated step-by-step in response to incoming impulses, an impulse sender for transmitting outgoing impulses, a stop member carried by said sender moved over a path corresponding to that of the registering member, a plurality of pins arranged in the path of said registering member,

and a magnet energized throughout each train of incoming impulses for lifting said registering member clear of said pins and deenerglzed at the end of each train to cause said registering means to displace a corresponding pin in the path of said stop member.

14. In a repeater as claimed in claim 13 including means on said stop member for arresting the movement thereof in response to said last means engaging said displaced pin, and means for operating said last means to restore said displaced pin to continue the movement of said stop member.

15. In a repeater as claimed in claim 13 including a stepped head mounted on said stop member for arresting the movement of said stop member in response to said head engaging said displaced pin, and an electromagnet for axially moving said stepped head to restore said displaced pin in response to its energization.

16. In a repeater as claimed in claim 13 including a circuit for controlling the transmitting operation, said circuit completed over said disfrom one position to its next position in response placed pin.

17. In a repeater as claimed in claim 13 including an eelctromagnet and means for operating said registering member one step on each deenergization of said electromagnet, and a circuit for energizing said registering member lifting magnet completed prior to the deenergization of said stepping electromagnet.

18. In a repeater, means for registering incoming trains oi. impulses, means for transmiton said governor in case the position of said cup is altered.

20. In a register sender, a movable member having a plurality of positions, movable pins arranged in the path of said member, there being a movable pin for each position of said member, means formoving said member one step to each incoming impulse received, said member displacing the pins corresponding to the positions occupied by said member at the end of each series ofincoming impulses, a sending member operable in the path of said pins, said sending member having a position corresponding to each position of. said movable member, means for operating said sending member, means controlled by said displaced pins for stopping said sending member in the positions corresponding to the displaced pins, means for restoring said displaced pins in response to said sending member being stopped in said positions, and an impulsev transmitting means controlled by said sending member for transmitting a series of outgoing imsuccessive movement of said second movable member, and means whereby said first membermay be in motion to register a subsequent digit at the same time that said second member is in motion to transmit the prior registered digit.

22. In a register sender, a first movable member, means for successively moving said first member to a plurality of positions in accordance with the number of impulses in each incoming series to register a plurality of incoming digits in response to the receipt of a plurality of series of incoming impulses, a second movable member, means responsive to said first means for successively moving said second member to positions corresponding to the successive registering positions assumed by said first member in registering said incoming digits, said second member moving concurrently with said first member or otherwise after the first registration by said first member, and an impulse transmitting means for transmitting an outgoing digit in accordance with each successive movement of said second member. v If 5 23. In an impulse receiving and transmitting device, a pair 01. coaxially rotatable members,

means controlled by the received impulses for causing one of the-members to be rotated and to mark certain of the positions occupied during said rotation, and means for causing the other member to be rotated and to control the transmission of impulses in accordance with the posi tions marked by the first member.

24. In an impulse receiving and transmittingmal position, a member capable 01'. being associated with the elements of said series in sequence responsive toincoming impulses and controlled in accordance with the incoming impulses to displace certain of the elements when associated therewith, a second member, motor means for the second member controlled by the incoming impulses to cause the second member to be associated with the elements of said series in the same sequence after an interval of time and to be influenced by displaced ones of said elements thereby to control the transmission of impulses.

JOHN WILLIAM MCCLEW.

CECIL ROBERT WOODLAND. 

